不同布苗法对河蟹早期溞状幼体变态率的影响

阐述了河蟹育苗过程中,清水布苗法和肥水布苗法的概念、特点和注意事项,分析了影响清水布苗法早期状幼体变态率的因素和对策;比较了微绿球藻和海链藻影响Z1变态率的原因,并分析了Z2死亡的原因和预防对策。通过对河蟹育苗过程中的Z1、Z2幼体的死亡原因分析,认为维持海链藻浓度在每毫升10万个左右可大大提高Z1、Z2幼体的变态成活率,节约育苗成本。同时,对同一水域不同时期育苗效果,有害藻类快速繁生现象作了分析。从幼体变态率、生产成本、稳定性等方面对两种布苗法作了全面比较,为河蟹育苗生产的科学安排提供了有益参考。

Effects of different breeding methods on the metamorphosis rate of early zoea of Eriocheir sinensis

The conceptions of clean water breeding and microalgae water breeding were developed and their characteristics and the precautions to be taken when applied to crab breeding were also discussed in this paper. In addition, the factors affecting the metamorphosis rate of early stages in crab zoea and the corresponding countermeasures were also analyzed. The causes to the different metamorphic rates of Z_1 by using Thalassiosira sp. or Nannochloropsis oculata as starter food in the breeding were compared and the causes to the high mortality of Z_2 and the precautions were analyzed. The results suggested that it be necessary to maintain the concentration of Thalassiosira sp. to achieve the high metamorphosis rate from Z_1 to Z_2 and Z_2 to Z_3 and to save the cost for the growth of harmful algae in the breeding waters were also analyzed. A complete comparison of two breeding methods in the Z_1 metamorphosis rate, production cost and stability etc. was conducted which was of great significance to the guidance of breeding of Eriocheir sinensis.